When Republican vice-presidential candidate Sarah Palin was interviewed by ABC's Charlie Gibson this week, she made a number of assertions that ABC itself found it necessary to fact-check.

During the last two minutes of the video below, ABC's Jake Tapper reviews a number of Palin's remarks. He confirms the interesting trivia point that you can see Russia from Alaska -- or at least from one of the most remote of Alaska's Aleutian islands, which is just a few miles from one of the most remote of Russia's -- but debunks Palin's denial that she has flipflopped on global warming since becoming John McCain's running-mate.

When Gibson asked Palin, "Do you still believe that global warming is not manmade?" she replied, "I believe that man's activities certainly can be contributing to the issue of global warming, climate change. ... John McCain and I agree that we got to do something about it, and we have to make sure that we're doing all we can to cut down on pollution."

"But isn't it critical as to whether or not it's manmade?" Gibson persisted. "Because what you do about it depends on whether it's manmade."

"That's why I'm attributing some of those activities to potentially causing some of the changes in the climate right now," Palin responded.

"Call me a cynic," commented Gibson, "but I hear a little bit of change in your policy. ... Sounds to me like you're adapting your position to Senator McCain's."

"Show me where I have ever said that there's absolute proof that nothing that man has ever conducted or engaged in has had any effect -- or no effect -- on climate change," challenged Palin. "I have not said that. I have said that my belief is that there is a cyclical nature of our planet."

Tapper handily meets Palin's challenge by citing a December 2007 article in a Fairbanks newspaper in which she was quoted as saying, "I'm not an Al Gore, doom-and-gloom environmentalist blaming the changes in our climate on human activity."

In his ABC blog, Tapper further notes that as recently as this August 28, Palin told an interviewer, "A changing environment will affect Alaska more than any other state, because of our location. I'm not one though who would attribute it to being man-made."

Tapper also fact-checked Palin's response to the question, "Have you ever met a foreign head of state."

Her response was, "I have not, and I think if you go back in history, and if you ask that question of many vice-presidents, they may have the same answer that I just gave you."

However, Tapper reports that all living vice-presidents, back to Walter Mondale in 1976, had met foreign heads of state before being elected. Internet posters have now suggested that the most recent vice-president not to have done so was Calvin Coolidge in 1920. Very much like Palin, Coolidge had been elected governor of Massachusetts just two years earlier, after having previously held only local offices.

It has been noted of Coolidge that when he succeeded to the presidency on the death of Warren Harding, he "was not a forceful leader in matters of foreign affairs and often deferred to his secretary of state." During his administration, the US retreated from involvement in world affairs, helping sow the seeds of World War II a decade later.

This video is from ABC's Good Morning America, broadcast September 12, 2008.